CROSS-REFERENCE TO RELATED APPLICATION
This application claims the priority benefit of Taiwan application serial no. 109112338, filed on Apr. 13, 2020. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
BACKGROUND
Field of the Disclosure
The disclosure relates to a heat dissipation fan, and particularly to a centrifugal heat dissipation fan.
Description of Related Art
Generally speaking, in order to improve the heat dissipation effect in the notebook computer, the methods include nothing more than reducing the thermal resistance of the system or improving the performance of the heat dissipation fan disposed therein. However, since the appearance of notebook computer becomes thinner and lighter and excessive configuration of heat dissipation holes is unfavorable, there is a large thermal resistance in the system, which reduces the air intake of the heat dissipation fan, and the air from the outside cannot easily enter the system to generate heat circulation required for heat dissipation.
In the meantime, the air gap between the blades of existing centrifugal fan is large, so it is not easy to control the air flow and backflow is very likely to occur, therefore the wind pressure is insufficient, which affects the heat dissipation efficiency. In addition, once the flow inlet is increased to increase the air intake, if the blade does not provide a corresponding structure, it is also likely to cause air leakage.
Accordingly, in the case where the thermal resistance of the existing system already exists, it is bound to provide effective means for raising the wind pressure and quantity of input air for the heat dissipation fan to effectively solve the above-mentioned problems.
SUMMARY OF THE DISCLOSURE
The disclosure provides a centrifugal heat dissipation fan, of which the shape of blade corresponds to the flow inlet of the housing, thereby increasing the quantity of input air and wind pressure to improve its heat dissipation performance.
The centrifugal heat dissipation fan of the disclosure includes a housing and an impeller. The housing has at least one flow inlet. The impeller is rotatably assembled in the housing along an axial direction. The impeller has a hub and multiple blades arranged around the hub. The flow inlet is located in the axial direction and faces the hub. Each of the blades has a wing tab adjacent to the flow inlet, the wing tab extends from a main surface of the blade toward another adjacent blade, and the wing tab has an inclined surface that faces the periphery of the flow inlet along the radial direction of the impeller.
Based on the above, the centrifugal heat dissipation fan is provided with a wing tab near the flow inlet of the blade, and the wing tab has an inclined surface facing the periphery of the flow inlet. In this manner, the inclined surface of the wing tab can also cooperate with the flow inlet to form a guide structure that guides the airflow outside the housing into the housing. Therefore, the presence of the wing tab and its adaptability with the flow inlet can effectively increase the quantity of input air of the centrifugal heat dissipation fan. Moreover, since the bending direction of the wing tab extends toward another adjacent blade, for the entire impeller, these wing tabs will provide a shielding effect for the inside of the housing, that is, the airflow that has been sucked into the housing can be continuously kept in the housing to be pressurized until the airflow comes out from the flow outlet.
In other words, if the existing impeller is adopted to cooperate with the flow inlet that is expanded to achieve the effect of increasing the quantity of input air, the above-mentioned air leakage problem will occur accordingly, and the pressurizing effect on the airflow inside the housing is also limited. However, if the impeller of centrifugal heat dissipation fan in the disclosure is adopted instead, corresponding to the characteristic of the shape of wing tab of the above-mentioned blade, it is possible to achieve the effect of guiding the external airflow into the housing, and pressurizing can be effectively performed on the airflow inside the housing, thereby effectively preventing the occurrence of air leakage mentioned above, such that the operation efficiency of the centrifugal heat dissipation fan can be enhanced.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a centrifugal heat dissipation fan according to an embodiment of the disclosure.
FIG. 2A is a perspective view of a blade of the centrifugal heat dissipation fan of FIG. 1.
FIG. 2B is a partial side view of the centrifugal heat dissipation fan of FIG. 1.
FIG. 3 is a top view of the blade of the centrifugal heat dissipation fan of FIG. 1.
FIG. 4A and FIG. 4B are partial side views of centrifugal heat dissipation fans according to different embodiments of the disclosure.
FIG. 5A is a schematic view of a centrifugal heat dissipation fan according to another embodiment of the disclosure.
FIG. 5B illustrates a part of the centrifugal heat dissipation fan of FIG. 5A from another viewing angle.
FIG. 6 is a schematic view of a centrifugal heat dissipation fan according to another embodiment of the disclosure.
DESCRIPTION OF EMBODIMENTS
FIG. 1 is an exploded view of a centrifugal heat dissipation fan according to an embodiment of the disclosure. FIG. 2A is a perspective view of a blade of the centrifugal heat dissipation fan of FIG. 1. FIG. 2B is a partial side view of the centrifugal heat dissipation fan of FIG. 1. In the meantime, the Cartesian coordinates X-Y-Z are provided to facilitate description of components. Please refer to FIG. 1, FIG. 2A and FIG. 2B at the same time. In the embodiment, the centrifugal heat dissipation fan 100 includes a housing 120 and an impeller 110. The housing 120 is composed of a base 122 and a top plate 121, and the housing 120 has flow inlets 122a and 121a. Here, the flow inlets 121a and 122a of the housing 120 respectively belong to the top plate 121 and the base 122, and the flow inlet 121a is the only one that cooperates with the impeller 110. Therefore, the flow inlet 121a will be the main object described subsequently, but the disclosure is not limited thereto. In another embodiment not shown, the impeller can also be designed in the manner that the shape of the blade corresponds to the flow inlet 122a to achieve the same effect as this embodiment. In other words, for the centrifugal heat dissipation fan 100, the operation mode thereof is that the airflow enters along the axial direction L1 and exits along the axial direction D1, which means that in the operation state of the impeller 110, the airflow outside the housing 120 enters the housing 120 through the flow inlets 121a and 122a, and exhausted from the housing 120 through the flow outlet 122b (composed of the combination of the top plate 121 and the base 122). Therefore, in this mode, the blades of the impeller cooperate with at least any one of the flow inlets to produce the same effect as this embodiment.
In this embodiment, the impeller 110 is rotatably assembled in the housing 120 along the axial direction L1, which is parallel to the Z-axis, and the impeller 110 has a hub 111 and multiple blades 112 arranged around the hub 111. The flow inlet 121a is located in the axial direction L1 and faces the hub 111. Each of the blades 112 has a wing tab 112a adjacent to the flow inlet 121a, the wing tab 112a extends from the main surface of the blade 112 toward another adjacent blade 112, and the wing tab 112a has an inclined surface V1, the inclined surface V1 faces the peripheral contour of the flow inlet 121a along the radial direction D1 of the impeller 110.
FIG. 3 is a top view of the blade of the centrifugal heat dissipation fan of FIG. 1. Please refer to FIG. 2A, FIG. 2B and FIG. 3 at the same time. In this embodiment, the blade 112 is divided into a first area A1, a second area A2 and a third area A3 along the radial direction D1. The first area A1 is connected to the hub 111, the second area A2 is connected between the first area A1 and the third area A3. The wing tab 112a extends from the second area A2 and is bent relative to the main surface of the blade 112, and the preferred bending angle is 90 degrees. Here, the size of the second area A2 in the axial direction L1 is larger than the size of the first area A1 in the axial direction L1, and the size of the second area A2 in the axial direction L1 is larger than the size of the third area A3 in the axial direction L1. In other words, in terms of a single blade 112, the second area A2 where the wing tab 112a is located is in a higher state than the first area A1 and the third area A3 of the blade 112, which means that the blade 112 in the second area A2 has a larger main surface in size. This is also equivalent to that, compared to the existing blades of nearly equal-sized main surface, the wing tab 112a of the blade 112 in this embodiment should be substantially established in a part with a larger main surface so as to be easily close to the flow inlet 121a, that is, after making the partial main surface of the blade 112 expand in the axial direction L1, the wing tab 112a is formed thereon. FIG. 2B holds the pressure so that the airflow does not easily come out.
Further, in the overall view of the impeller 110 of this embodiment, multiple blades 112 are substantially located on the same plane BS, and the plane BS of this embodiment is parallel to the X-Y plane, and the aforementioned axial direction L1 becomes the normal of the plane BS. Under the circumstances, for the blades 112, the heights h1 and h2 of the top of the second area A2 relative to the plane BS are larger than the height h3 of the top of the first area A1 relative to the plane BS, and the heights h1 and h2 of the top of the second area A2 relative to the plane BS will also be larger than the height h4 of the top of the third area A3 relative to the plane BS, as shown in FIG. 2B. That is, as compared with the first area A1 and the third area A3, the second area A2 with the wing tab 112a is closer to the periphery of the flow inlet 121a, such that the airflow F1 outside the housing 120 can be smoothly guided into the housing 120 when the impeller 110 is operating due to the channel structure formed by the flow inlet 121a and the inclined surface V1 of the wing tab 112a.
Furthermore, in this embodiment, the height of the wing tab 112a relative to the plane BS gradually decreases along the radial direction D1. Please refer to FIG. 2B and FIG. 3 at the same time, with respect to the rotation center of the hub 111 (that is, the axial direction L1), the wing tab 112a has an outer diameter R2 and an inner diameter R1 in the radial direction D1 (here, the axial direction L1 is used as a reference, the radii of the wing tab 112a at both ends in the radial direction D1 are shown as an example), and the outer diameter R2 is larger than the inner diameter R1. Corresponding to FIG. 2, it can be clearly seen that the height h2 corresponding to the outer diameter R2 is smaller than the height h1 corresponding to the inner diameter R1, and gradually decreases from the inner diameter R1 to the outer diameter R2, wherein the inner diameter R1 is smaller than the radius R3 of the flow inlet 121a, and the radius R3 of the flow inlet 121a is smaller than the outer diameter R2 of the wing tab 112a, that is, a part of the wing tab 112a is covered by the top plate 121, the inclined surface V1 is formed in cooperation with the size described above, and the inclined surface V1 is designed to form a channel structure for guiding the airflow F1 with the flow inlet 121a. Moreover, since the wing tab 112a and the flow inlet 121a have the above-mentioned corresponding relationship, the centrifugal heat dissipation fan 100 can prevent the airflow in the housing 120 from leaking, and has the effect of maintaining the wind pressure.
FIG. 4A and FIG. 4B are partial side views of centrifugal heat dissipation fans according to different embodiments of the disclosure. Please refer to FIG. 4A first. Different from the previous embodiment, the outer diameter R2 of the wing tab 112a is smaller than the radius R4 of the flow inlet 121a, that is, the wing tab 112a is completely exposed from the flow inlet 121a, but the flow inlet 121a along with the inclined surface V1 of the wing tab 112a still form a contour that is gradually decreased from the outer part of the housing 120 toward the inner part of the housing 120. Therefore, at the flow outlet 122b (shown in FIG. 1) of the housing 120 or a position adjacent thereto, since the airflow inside the housing 120 is exhausted, the airflow F1 on the outside can be smoothly guided into the housing 120 through the flow inlet 121a, thereby increasing the quantity of input air of the centrifugal heat dissipation fan 100.
Please refer to FIG. 4B, which is different from the previous embodiment in that the height of the wing tab 112a relative to the plane BS is larger than the height of the flow inlet 121a relative to the plane BS, as shown in the figure. There is a protruding gap G1 at the wing tab 112a relative to the top plate 121, and such configuration can further increase the quantity of input air and wind pressure. In other words, the blade 412 of this embodiment allows the second area A21 to further expand the main surface along the axial direction L1, so that the wing tab 112a can protrude from the flow inlet 121a. However, the same as the previous embodiment, the inclined surface V1 of the wing tab 112a can still correspond to the periphery of the flow inlet 121a to form a tapered contour, which is also advantageous for guiding the external airflow F1 of the housing 120 into the housing 120.
Based on the above embodiments, in general, the impeller 110 of the disclosure expands along the axial direction L1 in the second area A2 or A21 of its main surface 112 or 412, such that the wing tap 112a thereon can be adjacent to the flow inlet 121a, and thus the inclined surface V1 of the wing tab 112a can be close to the periphery of the flow inlet 121a to form a tapered contour, thereby increasing the quantity of input air and wind pressure of the centrifugal heat dissipation fan 100. Meanwhile, the wing tab 112a has the outer diameter R2 and the inner diameter R1 along the radial direction D1, which allows the designer to make adjustment to the desired quantity of input air and wind pressure. Here, the quantity of input air of the centrifugal heat dissipation fan 100 is proportional to the inner diameter R1, and the wind pressure of the centrifugal heat dissipation fan 100 is inversely proportional to the inner diameter R1. Briefly, please refer to FIG. 3, the smaller the inner diameter R1 of the wing tab 112a, the larger the radial size of the wing tab 112a, as the inner diameter R5 shown in the figure, and which is equivalent to adding the area shown by diagonal lines. For the internal space of the housing 120, the wing tag 112b formed as described above can be seen as increasing the area covering the internal space, and also improving the retention rate of the airflow in the internal space, so that the wind pressure of the centrifugal heat dissipation fan 100 can be improved.
In the centrifugal heat dissipation fan 100 of this embodiment, the diameter of the flow inlet 121a is smaller than the diameter of the impeller 110, and based on the example that the diameter of the flow inlet 121a is 80% of the diameter of the impeller 110, if the impeller of existing technology is adopted, when the flow inlet is further enlarged to increase the quantity of input air, the blade of the impeller cannot cooperate with the above configuration and thus the problem the air leakage will occur. On the contrary, if the impeller 110 in the above-mentioned embodiment of the disclosure is adopted, that is, the blade 112 or 412 has the wing tab 112a, it is possible to further reduce the distance between the impeller 110 and the housing 120 at the flow inlet 121a. In other words, the impeller 110 of the disclosure, with the configuration of the wing tab 112a on the blade 112 or 412, changes the original fixed shielding structure (the local substance of the top plate 121 at the periphery of the flow inlet 121a) into a movable shielding structure (i.e., wing tab 112a), thereby expanding the flow inlet to increase the quantity of input air while improving the required wind pressure. Similarly, even without enlarging the flow inlet, the blade 112 with the wing tab 112a can achieve the effect of increasing the quantity of input air and wind pressure.
FIG. 5A is a schematic view of a centrifugal heat dissipation fan according to another embodiment of the disclosure. FIG. 5B illustrates a part of the centrifugal heat dissipation fan of FIG. 5A from another viewing angle. Please refer to FIG. 5A and FIG. 5B at the same time. In the impeller 210 of this embodiment, the wing tab 212a of each blade 212 extends from the main surface of the blade 212 toward another adjacent blade 212 and is connected to another wing tab 212a of another blade 212, so that the wing tabs 212a of the impeller 210 are connected to each other in a ring shape, and the wing tabs 212a arranged in ring shape also have an inclined surface V2 to correspond to the flow inlet 121a (shown in FIG. 1) facing the housing 120, such that the impeller 210 can effectively improve its structural strength while achieving the same effect as the previous embodiment. The disclosure provides no limitation to the connection manner of the wing tab 212a, which may be fastened one by one by the fasteners formed by the metal blades in the stamping process, or by connecting the blades 212 through plastic materials by injection in the mold. Certainly, the blade 212 and its wing tab 212a can also be completed by one-time injection molding through plastic materials.
FIG. 6 is a schematic view of a centrifugal heat dissipation fan according to another embodiment of the disclosure. Referring to FIG. 6, in the impeller 310 of this embodiment, the blade 312 disposed at the hub 111 already has the relevant features described in the previous embodiment, for example, the wing tabs 312a adjacent to each other are connected together and form a ring shape, and is equally provided with an inclined surface V3 corresponding to the flow inlet 121a. The difference lies in that the blade 312 of this embodiment also has a broken blade edge 312c and another wing tab 312b, wherein the broken blade edge 312c is substantially located in the third area A3 of the blade 312 (as shown in FIG. 2A and FIG. 2B). The wing tab 312b and the broken blade edge 312c are respectively at different edges of the third area A3 (the broken blade edge 312c is adjacently connected between a pair of wing tabs 312b), wherein the wing tab 312b has a swept-back design with respect to the rotation direction (see counterclockwise arrow as shown in the figure) of the impeller 310. Here, the blade 312, the broken blade edge 312c, and the wing tab 312b are formed by stamping and bending a metal plate. Accordingly, not only that the blade 312 of this embodiment retains the features and effects of the previous embodiment, the wing tab 312b and the broken blade edge 312c can further disperse and weaken the vortex formed at the end of the blade 312, so as to reduce the disturbance caused by the rotation of the blade 312 to the surrounding air, thereby achieving the effects of improving operation efficiency and reducing noise.
In summary, in the above embodiments of the disclosure, the centrifugal heat dissipation fan is provided with a wing tab near the flow inlet of the blade, and the wing tab has an inclined surface facing the periphery of the flow inlet. In this manner, the inclined surface of the wing tab can also cooperate with the flow inlet to form a guide structure that guides the airflow outside the housing into the housing, so the presence of the wing tab and its adaptability to the flow inlet can effectively improve the quantity of input air of the centrifugal heat dissipation fan. In the meantime, because the bending direction of the wing tab extends toward another adjacent blade, for the entire impeller, these wing tabs will provide a shielding effect on the inside of the housing, that is, the airflow that has been sucked into the housing can be continuously kept in the housing to be pressurized until it comes out from the flow outlet. In addition, the designer can adjust the inner diameter and outer diameter of the wing tab and the height of the wing tab relative to the plane where the blade is located depending on different needs for the quantity of input air and wind pressure.
In other words, if the existing impeller is adopted to cooperate with the flow inlet that is expanded to achieve the effect of increasing the quantity of input air, the above-mentioned air leakage problem will occur accordingly, and the pressurizing effect on the airflow inside the housing is also limited. However, if the impeller of centrifugal heat dissipation fan in the disclosure is adopted instead, corresponding to the characteristic of the shape of wing tab of the above-mentioned blade, it is possible to achieve the effect of guiding the external airflow into the housing, and pressurizing can be effectively performed on the airflow inside the housing, thereby effectively preventing the occurrence of air leakage mentioned above, such that the operation efficiency of the centrifugal heat dissipation fan can be enhanced.
Patent Grant
11629725
